Dial for indicating devices



June 15 1926.

o. w. as:

DIAL FOR INDICATING DEVICES vFiled March 30 1922 INVENTOR.

Y A'ITI'ORNEY Patented June 15, 1926.

UNITED STATES 1,588,418, PATENT orcE.

orro W. nurse, or BiuneEr'on'r, oonniiorrcur, AssIGNoR 'ro MANNING, MAXWELL & MOORE, INC., on NEW YORK, 1v. 1, aooaroneriolv on NEW- JERSEY.

DIAL roe INDICATING' DEVICES.

Application filed March 30, 1922. Serial No. 548,261.

This invention relates to dials for indicating devices, and also to a method of makmg the same.

The invention has for its general objectv the improvement and perfection of'dial con struction resulting in an article which is durable and accurate, and capable of manufacture by a simple process resulting in important production economies.

Another object is the provision of a dial of paper, or the like, of improved construction in which errors are reduced to a negligible quantity.

Another object is to provide an improved method of manufacture by which uniform dials may be quickly and economically made in small quantities.

Other objects will be in part pointed out in connection with the following detailed description and will be in part obvious as the description proceeds. V

In the accompanying drawings in which an illustrative but preferred embodiment of the improved dial is shown,

Figure 1 shows a blank for the dial base;

Fig. 2 shows a sheet of photographic paper for the dial face;

3 shows the base and face sheet assembled to form a'dial blank;

Fig. 4; shows the dial blank with locating openings punched therein; and

Fig. shows the completed dial.

Referring now more particularly to the embodiment disclosed in the drawings, a.

dial of the type employed for indicating or measuring instruments of various descriptions and constructed in accordance with the invention is shown. This dial comprises a separate base-plate 1 or support, preferably of sheet aluminum or other metal, forming a light but rigid support to which is attached a dial face-sheet 2 of paper or similar material, and having 'the'dial scale and other indicia aflixed thereon. This dial sheet is preferably made of photographic paper of good quality, free from discoloring or other injurious agents, and as little subject to stretching or other distortion asv possible when subjected to dampening such as by the application of an adhesive substance thereto, or to other d1stort1on under var ous conditions of manufacture, in use. 7* impossible, however, to secure paper @iit across the grain.

e1; from such. dismisses, and. this invention provides means for minimizing errors due thereto, as will fully appear hereinafte The aiiixing of scale 3 and the other desired indicia to the face-sheet .2, is accomplished by preparing a suitable negative from which they may be readily transferred. Photographically this transfer is conveniently effected by exposing suitable sensitized paper to a photographic negative in a suitable light in the ordinary manner: When made, the face-sheet with its indicia is secured to the metallic supporting base by an adhesive substance, suchas cement or glue, which holds the parts securely and permanently in smooth contacting-relationship with each other.* This forms a composite blank as shown in Fig. 3 from which the dial is subsequently cut as for example by the use of suitable dies, resulting in a light anddurable product. I

The dial above described is made most conveniently and economically, and the errors and inaccuracies due to stretching of the paper, etc, are reduced to a minimum by a process which will now be described. When photographic paper upon which the scale is fixed is subjected to moisture as,

for example, when cement or glue is applied, a certain amount of'stretching' takes place, and this stretching is much greater in the direction of the grain of the paper than V For example, a certain grade of photographic paper having a dimension in the direction of the grain which measures 5 when dry, will stretch so that this dimension measures about 5 when glued to the'metal; this represents an in crease of diameter in this direction of about 2 70. The errors due to this stretching are partially compensated for by making the negative, and consequently the print,

enough smaller than the required size to compensate forthis stretching. Due to unequal stretching in different directions, however, there will still be a distortion of the print, resulting in errors in the dial scale if not'corrected. These errors are minimized and equalized by locating the scale on the completed dial in properly centered position. I This is accomplished by so positioning the dial blank vfor trimming as to compensate and equalize 'upon the scale the distertien mentiniistl; The positioning is et mensions. .5 and 6 111- Fig. 3 of the drawing.

fectcd by means of one or more location spots'or indications shown at 4 on the print 2, thenegative having a corresponding spot which is transferred to the print in the printing process. This spot will be located preferably at or near the center of curvature of the dial scale, to coincide with the pivotal mounting of the index of the instrument on which the dial is mounted. This spot can be located at some other point on the print. bearing a known relation to the center of curvature of the scale, but it is found more convenient in practice to lo cate it at the center.

It may be desirable to have one or more additional location spots or indications so as to aid in definitely locating the dial for blanking in the punching or other apparatus employed in reducing the blank to final di- 1W0 such spots are indicated at Spots 5 and-6 hear a definite relation to spot l, and these together form indications for definitely positioning the dial with respect to the dies in the punching apparatus. These locating spots are preferably positioned outside the area of the completed dial as shown, but not necessarily so. By this method-oflocat-v ingf the position of the indications it will be seen that errors in the scale due to distortion of the dial paper will be equalized and distributed over the scale so as to be reduced to anegligible quantity at any given part of the scale. It will be understood that this method of minimizing errors is applicable to: diiierent shapes of dials having indicating scales of different forms and positioned ditferently on the dial and is not limited to the form of dial shown in the drawing.

Afterth'e various markings are fixed on the dial face as described, the paper is moistened equally throughout to make it pliable and anadhesive substance'is brushed on It is then placed on the face ofthe back. the metallic base, thoroughly flattened out in position, and the superfluous moisture removed. This provides a composite blank which is then thoroughly dried.- It will be understood that at this time the dial is not blanked or punched to size, nor have any the hole 4* is adapted-to receive one of the locating pins. It will be understood also that the dial blank may be prepared. in some other Way than perforating in accordance with the locatin indications such as oil proo-iied to prevent moisture from penetrat ing the paper or the oints between the paper and its supporting base. For this purpose dip lacqi-iering is preferable because a com plete protective coating is thus securedand no .lllOlStlllB can penetrate to the paper or glue.

Having described my inventioi'i, what I claim as new and desire to secure by Letters Patent, is.: v

1. A composite blank for use in making dials comprising apiece of stiff sheet mate rial of a. size greater than that of the completed dial and constituting. a back, and a piece of paper constituting the dial face se cured to the back saidpaper boa -in-g'plioto graphically impressed scale indicia, thecomposite blank being provided withspaced position'ing'openings outside the limits of the completed dial for accurately positioning the blank during a subsequent trimming operation. g

2. That process of making dials for measuring instruments which comprises preparing a photographic print bearing the indicia to appear on the face of the dial, securing the print to a supporting plate by the use of adh sivc, and subjecting the composite blank thus formed to apunching operation whereby imultaneously to reduce the print and supporting plate to the size and shape 01" the completed dial. V

That method of producing dials for measuring instruments which comprises-pro viding a face sheet with scale indications and with one or more location indicatioi cementing the sheet to asupporting base to fornii a composite blank, positioning the composite blank r lativcly to trimming means by reference to the location indications, and trimming siurpl'us material from said blank to reduce the latter to the dimensions oi the completed dial.

ln testimony whereof I aliix my signature.

OTTO W. nurse; 

